If he can't control his wife, can he run the government? That question has long bedeviled Canadian Prime Minister Pierre Elliott Trudeau and, as the May 22 election approaches, it is still a hot question north of the border. But these days it is also being directed at Tory opposition leader Joe Clark, 39, who is constantly being pressed as to why his wife insists on using her maiden name. Maureen McTeer naturally answers for herself. "I decided as a teenager I would use my family name," she says. "I always knew I would marry a man strong enough to accept that and not be threatened by it."

Clark is giving Trudeau, 59, the fight of his 11-year career as PM in a campaign marked by issues like unemployment, big deficits, spiraling prices and the threat of Quebec secession. But on another level it is a squaring-off of wives: the absent, flakier-than-ever Margaret, 30, whose steamy confessional Beyond Reason has been vying awkwardly with her husband for campaign-season headlines; and Maureen, 27, an indefatigable campaigner who nevertheless has not let her husband's career deflect her own ambitions as a lawyer. The two women have much in common—their independence, attractiveness and youth—and both were into politics early. Maureen, the daughter of a civil servant and Tory organizer who died last year, began in her teens; Margaret, the child of a onetime Liberal cabinet minister, at birth. Yet one difference sets them decisively apart. The estranged Mme. Trudeau recently told an interviewer she hoped, for the children's sake, Pierre would lose. McTeer vehemently dismisses such worries for their 2-year-old Catherine.

Clark can use all the help he can get—a lusterless bumbler on the hustings, he has been described as Canada's Jerry Ford, and his campaign promises have led Trudeau to tag him the "Seven-Billion-Dollar Man." Still, he has managed to stay even with Trudeau in the polls—and "Maureen McTeer, Joe Clark's wife," as she is billed in appearances, is one reason why.

When they met in 1972 she was an undergraduate at the University of Ottawa working as a volunteer researcher for his party. He became an MP that year, and Maureen went to work for him part-time. By the time they married in 1973 she was in law school at Ottawa. "She took so much time off in the spring of 1976 to help Joe win the party leadership that she flunked her year at law school," recalls an aide. (Clark, who himself flunked out of law school in Nova Scotia, never went back.)

McTeer had to take more time off from school to nurse daughter Catherine, but she graduated last year and has begun her year of "articling"—an apprenticeship required before taking the Canadian bar exam. "I want to have a law career and be good at it," she says. "I don't want to do too many things that will jeopardize that opportunity." Her husband's election would, however, table any plans she had for entering politics herself: "I think it's important that I have my career, and my husband has his."

Mme. Trudeau, of course, felt the same way. Neither standard-bearer is talking about Margaret's bellyflops in photography or acting—or her constant indiscretions. Pierre, for his part, has probably benefited from his stoic refusal to comment on her at all and his managing of their three children. Clark's supporters make the point by implication. "Maureen McTeer is a good, sturdy girl," said former Tory leader Robert Stanfield not long ago, "with her head screwed on tight."